1. Field of the Invention
The present invention relates to a wireless power transmitting/receiving apparatus. More particularly, the present invention relates to a soft magnetic layer, and a receiving antenna and wireless power receiving apparatus including the same.
2. Discussion of Related Art
As wireless communication technology develops, there is increasing interest in wireless power transmitting/receiving technology in which power is wirelessly supplied to an electronic apparatus. The wireless power transmitting/receiving technology may be variously applied in power supply to home electronics, electric cars, subway cars, etc. as well as battery charging of portable terminals.
In a common wireless power transmitting/receiving technology, the principle of magnetic induction or magnetic resonance is used. For example, when electric energy is applied to a transmission antenna of a wireless power transmission apparatus, the transmission antenna converts the electric energy to electromagnetic energy, and radiates the electromagnetic energy. In addition, a receiving antenna of a wireless power receiving apparatus receives the electromagnetic energy radiated from the transmission antenna, and converts the electromagnetic energy to electric energy.
Here, in order to increase power transmitting/receiving efficiency, energy loss between the wireless power transmission apparatus and the wireless power receiving apparatus needs to be minimized. To do this, the transmission antenna and the receiving antenna need to be mutually aligned within an effective distance. In addition, the electromagnetic energy radiated from the transmission antenna needs to be collected in a direction of the receiving antenna by configuring the transmission antenna and the receiving antenna to include a soft magnetic material.
The soft magnetic material for the receiving antenna may be changed depending on the location of transmission antenna, the type of soft magnetic material for the transmission antenna, the effect of a permanent magnet included in the wireless power transmission apparatus, etc.
Generally, as the soft magnetic material for the receiving antenna, a composite containing a metallic material (e.g. Fe—Si—Al, Fe—Si—Cr, and Fe—Si—B) having soft magnetic characteristics, a resin, and an additive, or a Ni—Zn ferrite material may be used. When using the composite containing the metallic material, there are problems in that a required level of power transmission efficiency is not obtained, and the price is high. In addition, when using the Ni—Zn ferrite material, although high frequency characteristics are good, there is a problem in that low frequency characteristics are not good.